In the 3rd Generation Partnership Project (3GPP), which is a mobile communication system standardization project, discontinuous reception (DRX) is specified as an intermittent reception technique for reducing power consumption of a radio terminal. A radio terminal that performs the DRX operation intermittently monitors a downlink control channel. A cycle with which the downlink control channel is monitored is referred to as a “DRX cycle.”
In recent years, machine type communication (MTC) in which a radio terminal performs communication in a mobile communication system with no human intervention has attracted attention. Under such a circumstance, a proposal to newly introduce an extended DRX cycle longer than an existing DRX cycle and further reduce the power consumption is under review. DRX using an extended DRX cycle is referred to as “extended DRX.”